Open source monitoring tools in 2026
Check that services, hosts, networks and scheduled jobs are up and healthy, from inside and outside. This list has 67 monitoring tools. Of these, 67 are open source, 67 have a free plan and 67 can be self-hosted. Checked by hand on 30 September 2026.
- 1
Akvorado
Flow collector and visualizer that receives NetFlow, IPFIX and sFlow, enriches flows with interface and routing data, stores them in ClickHouse and shows them in a web UI.
- 2
Apache HertzBeat
Agentless monitoring system from the Apache Software Foundation that polls servers, databases, middleware, network devices and websites through templates, with built-in alerting.
- 3
Beszel
Lightweight self-hosted server monitor: a small agent reports CPU, memory, disk, network and Docker container stats to a hub that keeps history and sends alerts.
- 4
Blackbox exporter
Prometheus exporter that probes endpoints over HTTP, HTTPS, DNS, TCP, ICMP and gRPC and exposes the results as metrics you can alert on.
- 5
Botkube
Kubernetes ChatOps bot that posts cluster events and alerts to Slack, Discord or Mattermost and lets you run kubectl from chat.
- 6
Cacti
Network graphing tool built on RRDtool: polls devices over SNMP or scripts and draws long-term graphs of traffic and system metrics.
- 7
cAdvisor
Google's container advisor: a daemon that collects resource usage and performance data for running containers and exposes it to Prometheus. Built into the kubelet.
- 8
Centreon
IT infrastructure and network monitoring platform that runs Nagios-compatible plugins, offered as open source and as commercial on-premises and cloud editions.
- 9
CheckCle
Self-hosted open source monitor for HTTP, ping, TCP and DNS uptime, server metrics and SSL expiry, with incident tracking and public status pages.
- 10
Checkmate
Self-hosted open source monitor from BlueWave Labs for HTTP, ping, TCP port, DNS, WebSocket and gRPC checks, with an optional agent for server hardware metrics and status pages.
- 11
Checkmk
Infrastructure monitoring for servers, networks, cloud and containers with automatic service discovery; the base edition is open source and paid editions add more.
- 12
Cloudprober
Active prober that started at Google: runs HTTP, DNS, ping, TCP, gRPC and custom probes and exports latency and success metrics to Prometheus and other backends.
- 13
Coroot
Open source observability that uses eBPF to build service maps and collect metrics, logs, traces and profiles without code changes, with root-cause hints.
- 14
Dozzle
Small web UI that streams and searches live Docker container logs across hosts, with no log storage. Optional Dozzle Cloud adds grouped alerts and log analysis.
- 15
Freelens
Community-maintained open source Kubernetes desktop IDE, forked from OpenLens, for managing clusters and viewing workloads, metrics and logs.
- 16
Gatus
Health dashboard configured in YAML: checks HTTP, TCP, DNS, ICMP and other endpoints against conditions on status, body and latency, and alerts to many channels. Also sold as a hosted service.
- 17
Glances
Cross-platform system monitor in Python that shows CPU, memory, disk, network, processes and containers in a terminal, a web UI or a REST API.
- 18
Headlamp
Kubernetes web UI and desktop app, now a Kubernetes SIG UI project, for browsing cluster resources, logs and events, extensible with plugins.
- 19
Healthchecks.io
Cron job and heartbeat monitoring: each job pings a unique URL, and a missed or late ping sends an alert. The server is open source and can be self-hosted.
- 20
Hubble
Network observability layer for Cilium that shows service dependencies, network flows and DNS and HTTP traffic between Kubernetes workloads, using eBPF.
- 21
Icinga
Monitoring system that grew out of Nagios: checks hosts and services with plugins, scales across distributed zones, and is configured through files or an API.
- 22
Inspektor Gadget
CNCF project of eBPF-based tools (gadgets) for inspecting and debugging Kubernetes workloads and Linux hosts, from network traces to process and file activity.
- 23
K8sGPT
CLI and operator that scans Kubernetes clusters for problems and explains them in plain language using an LLM backend of your choice. CNCF sandbox project.
- 24
k9s
Terminal UI for Kubernetes that lists and watches cluster resources in real time and lets you view logs, exec into pods and act on resources with keystrokes.
- 25
kube-state-metrics
Kubernetes add-on that listens to the API server and exposes the state of objects such as deployments, pods and nodes as Prometheus metrics.
- 26
Kubernetes Dashboard
The former official web UI for viewing and managing workloads and resources in a Kubernetes cluster.
- 27
kubernetes-event-exporter
Exports Kubernetes events to sinks such as Slack, Opsgenie, Elasticsearch, Kafka or webhooks, so events can be kept and alerted on.
- 28
Kubeshark
Captures and dissects API traffic between Kubernetes pods (HTTP, gRPC, Kafka, DNS and more) so you can inspect requests cluster-wide, like Wireshark for Kubernetes.
- 29
Kubewatch
Kubernetes watcher that reports resource changes in the cluster to Slack, Mattermost and other chat channels or to a webhook.
- 30
Kuvasz Uptime
Self-hosted uptime and SSL certificate monitor with brandable public or private status pages, maintenance windows and alerts to common chat and email channels.
- 31
LibreNMS
Network monitoring system with automatic SNMP discovery, graphs and alerting, supporting a long list of network hardware vendors.
- 32
Metrics Server
Cluster-wide aggregator of CPU and memory usage from kubelets, serving the Metrics API used by kubectl top and the Horizontal Pod Autoscaler.
- 33
Monika
Command-line synthetic monitor from Hyperjump: define HTTP, TCP, ping and database probes in a YAML file, run them anywhere, and send alerts to many channels.
- 34
Monit
Small Unix daemon that watches processes, files, filesystems and hosts and can restart a service or send an alert when a check fails. M/Monit is the paid central console.
- 35
Munin
Networked resource monitoring: a master polls lightweight node agents and their plugins and graphs server metrics over time.
- 36
mysqld_exporter
Official Prometheus exporter for MySQL and MariaDB that exposes server status, InnoDB and replication metrics.
- 37
Naemon
Fork of the Nagios 4 core with performance improvements, compatible with Nagios configuration files and plugins.
- 38
Nagios Core
Long-running open source host and service checker with a large plugin ecosystem; Nagios XI is the commercial edition built on it.
- 39
NetAlertX
Self-hosted scanner that discovers devices on your network and alerts when new, unknown or offline devices appear.
- 40
Netdata
Per-second metrics for servers, containers and applications from an agent with built-in dashboards and alerts, plus the optional hosted Netdata Cloud.
- 41
Netdisco
Open source network management tool that discovers switches and routers over SNMP and lets you locate devices by MAC or IP, browse ports and track inventory.
- 42
NetXMS
Network and infrastructure management system with SNMP discovery, network maps, server agents and event correlation; an Enterprise edition adds support and features.
- 43
Nezha
Self-hosted monitoring panel for small server fleets: agents report host status and resource use, and the panel can run uptime checks and remote tasks.
- 44
ntopng
Web-based network traffic monitor that analyses packets or flows to show top talkers, applications, hosts and alerts. Open source Community edition with paid Pro and Enterprise versions.
- 45
openITCOCKPIT
Monitoring suite that manages Naemon checks through a web interface, with Checkmk and Grafana integration; community and enterprise editions.
- 46
OpenNMS
Network management platform for fault and performance monitoring at scale; Horizon is the open source edition and Meridian the supported one.
- 47
Pandora FMS
Monitoring for servers, networks, applications and logs, with an open source community edition and a commercial enterprise edition.
- 48
Peekaping
Self-hosted uptime monitor written in Go with a React UI, built as an alternative to Uptime Kuma, with status pages and pluggable notification channels.
- 49
Percona Monitoring and Management
Open source monitoring for MySQL, PostgreSQL, MongoDB and Valkey: a server and client agents collect metrics and query analytics, with Grafana-based dashboards and alerting.
- 50
pgBadger
PostgreSQL log analyzer that turns server logs into HTML reports on slow queries, errors, locks, checkpoints and connections.
- 51
PgHero
Small web dashboard for Postgres that shows slow queries, index usage, table bloat and connection counts. Runs as a Rails engine or a Docker container.
- 52
pgMonitor
Crunchy Data's bundle of Prometheus exporter queries, alert rules and Grafana dashboards for monitoring PostgreSQL and its hosts.
- 53
pgwatch
PostgreSQL monitoring from Cybertec that gathers metrics with SQL queries and stores them in Postgres or Prometheus for the bundled Grafana dashboards.
- 54
Pixie
Kubernetes observability that uses eBPF to capture service traffic, metrics and CPU profiles automatically; a CNCF sandbox project.
- 55
pmacct
Set of passive network monitoring daemons that collect NetFlow, IPFIX, sFlow, BGP and BMP data and export traffic accounting to databases or message brokers.
- 56
postgres_exporter
Prometheus exporter that exposes PostgreSQL server statistics as metrics for Prometheus to scrape and alert on.
- 57
PoWA
PostgreSQL Workload Analyzer: collects query statistics from pg_stat_statements and related extensions into a history you browse in a web UI, with index suggestions.
- 58
Prometheus Operator
Kubernetes operator that deploys and configures Prometheus and Alertmanager from custom resources. Its kube-prometheus project and the kube-prometheus-stack Helm chart bundle a full cluster monitoring setup.
- 59
Robusta
Kubernetes alert enrichment and routing on top of Prometheus: adds pod logs, events and graphs to alerts and sends them to Slack, Teams and other sinks. Open source core plus a paid SaaS.
- 60
Runitor
Command runner for Healthchecks.io: wraps a job, sends start, success or failure pings with its output, and also works with self-hosted Healthchecks.
- 61
Scrutiny
Web dashboard for hard drive S.M.A.R.T. data that tracks disk health over time and warns before a drive fails.
- 62
Sensu
Monitoring event pipeline for dynamic infrastructure: agents run checks, and filters and handlers route the results to alerting and metrics tools, all managed as code.
- 63
SmokePing
Latency monitor that probes hosts continuously and graphs latency and packet loss distribution over time.
- 64
Uptime Kuma
Self-hosted monitor for HTTP, keyword, TCP, ping, DNS, Docker and push checks, with status pages and dozens of notification integrations.
- 65
UptimeFlare
Serverless uptime monitor and status page that runs on Cloudflare Workers, checking HTTP and TCP endpoints and sending notifications.
- 66
Xymon
Long-standing system and network monitor that shows host and service status on a color-coded web page, with client agents for host data.
- 67
Zabbix
Open source monitoring for networks, servers, VMs, applications and cloud, using agents, SNMP and templates with trigger-based alerting; Zabbix Cloud is the hosted option.
Side by side
| Tool | Pricing | Free plan | Open source | Self-hosted |
|---|---|---|---|---|
| Akvorado | Free | Yes | Yes | Yes |
| Apache HertzBeat | Free | Yes | Yes | Yes |
| Beszel | Free | Yes | Yes | Yes |
| Blackbox exporter | Free | Yes | Yes | Yes |
| Botkube | Free | Yes | Yes | Yes |
| Cacti | Free | Yes | Yes | Yes |
| cAdvisor | Free | Yes | Yes | Yes |
| Centreon | Free plan | Yes | Yes | Yes |
| CheckCle | Free | Yes | Yes | Yes |
| Checkmate | Free | Yes | Yes | Yes |
| Checkmk | Free plan | Yes | Yes | Yes |
| Cloudprober | Free | Yes | Yes | Yes |
| Coroot | Free plan | Yes | Yes | Yes |
| Dozzle | Free plan | Yes | Yes | Yes |
| Freelens | Free | Yes | Yes | Yes |
| Gatus | Free plan | Yes | Yes | Yes |
| Glances | Free | Yes | Yes | Yes |
| Headlamp | Free | Yes | Yes | Yes |
| Healthchecks.io | Free plan | 20 jobs | Yes | Yes |
| Hubble | Free | Yes | Yes | Yes |
| Icinga | Free plan | Yes | Yes | Yes |
| Inspektor Gadget | Free | Yes | Yes | Yes |
| K8sGPT | Free | Yes | Yes | Yes |
| k9s | Free | Yes | Yes | Yes |
| kube-state-metrics | Free | Yes | Yes | Yes |
| Kubernetes Dashboard | Free | Yes | Yes | Yes |
| kubernetes-event-exporter | Free | Yes | Yes | Yes |
| Kubeshark | Free plan | Community: up to 3 nodes and 60 pods | Yes | Yes |
| Kubewatch | Free | Yes | Yes | Yes |
| Kuvasz Uptime | Free | Yes | Yes | Yes |
| LibreNMS | Free | Yes | Yes | Yes |
| Metrics Server | Free | Yes | Yes | Yes |
| Monika | Free | Yes | Yes | Yes |
| Monit | Free plan | Yes | Yes | Yes |
| Munin | Free | Yes | Yes | Yes |
| mysqld_exporter | Free | Yes | Yes | Yes |
| Naemon | Free | Yes | Yes | Yes |
| Nagios Core | Free plan | Yes | Yes | Yes |
| NetAlertX | Free | Yes | Yes | Yes |
| Netdata | Free plan | 5 nodes, non-commercial use | Yes | Yes |
| Netdisco | Free | Yes | Yes | Yes |
| NetXMS | Free plan | Yes | Yes | Yes |
| Nezha | Free | Yes | Yes | Yes |
| ntopng | Free plan | Yes | Yes | Yes |
| openITCOCKPIT | Free plan | Yes | Yes | Yes |
| OpenNMS | Free plan | Yes | Yes | Yes |
| Pandora FMS | Free plan | Yes | Yes | Yes |
| Peekaping | Free | Yes | Yes | Yes |
| Percona Monitoring and Management | Free | Yes | Yes | Yes |
| pgBadger | Free | Yes | Yes | Yes |
| PgHero | Free | Yes | Yes | Yes |
| pgMonitor | Free | Yes | Yes | Yes |
| pgwatch | Free | Yes | Yes | Yes |
| Pixie | Free | Yes | Yes | Yes |
| pmacct | Free | Yes | Yes | Yes |
| postgres_exporter | Free | Yes | Yes | Yes |
| PoWA | Free | Yes | Yes | Yes |
| Prometheus Operator | Free | Yes | Yes | Yes |
| Robusta | Free plan | Yes | Yes | Yes |
| Runitor | Free | Yes | Yes | Yes |
| Scrutiny | Free | Yes | Yes | Yes |
| Sensu | Free plan | Yes | Yes | Yes |
| SmokePing | Free | Yes | Yes | Yes |
| Uptime Kuma | Free | Yes | Yes | Yes |
| UptimeFlare | Free | Yes | Yes | Yes |
| Xymon | Free | Yes | Yes | Yes |
| Zabbix | Free plan | Yes | Yes | Yes |
Plans and prices change; check each tool's own site before you decide.